Occlusal force, electromyographic activity of masticatory muscles and mandibular flexure of subjects with different facial types

Abstract

ObjectiveThe aim of this study was to evaluate whether vertical facial patterns influence maximal occlusal force (MOF), masticatory muscle electromyographic (EMG) activity, and medial mandibular flexure (MMF).Material and MethodsSeventy-eight dentate subjects were divided into 3 groups by Ricketts's analysis: brachyfacial, mesofacial and dolychofacial. Maximum occlusal force in the molar region was bilaterally measured with a force transducer. The electromyographic activities of the masseter and anterior temporal muscles were recorded during maximal voluntary clenching. Medial mandibular flexure was calculated by subtracting the intermolar distance of maximum opening or protrusion from the distance in the rest position. The data were analyzed using ANOVA followed by Tukey's HSD test. The significance level was set at 5%.ResultsData on maximum occlusal force showed that shorter faces had higher occlusal forces (P<0.0001). Brachyfacial subjects presented higher levels of masseter electromyographic activity and medial mandibular flexure, followed by the mesofacial and dolychofacial groups. Additionally, dolychofacial subjects showed significantly lower electromyographic temporalis activities (P<0.05).ConclusionWithin the limitations of the study, it may be concluded that maximum occlusal force, masticatory muscle activity and medial mandibular flexure were influenced by the vertical facial pattern.

Jaw-motor effects of experimental jaw-muscle pain and stress in patients with deep bite and matched control subjects

“…24 Subjects with a long-face pattern showed significantly lower EMG activity of the masticatory muscles compared to squareface pattern. [25][26][27] This is in disagreement with the findings in the present study. An explanation for this disagreement could be that the deep bite group in the present study had significantly more TMD symptoms and signs than the controls 15 and this might lead to a slightly decreased EMG activity as some previous studies have shown an association between EMG activity and TMD.…”

“…Previously, associations between EMG activity and malocclusion traits and between EMG activity and craniofacial morphology have been reported. [24][25][26][27] Patients with deep bite had significantly higher EMG activity of the masseter and temporalis muscles during mastication compared to other malocclusion traits. 24 Subjects with a long-face pattern showed significantly lower EMG activity of the masticatory muscles compared to squareface pattern.…”

Parkinson’s disease impairs masticatory function

“…Optocal was used to determine the X 50 because this material allows standardization of weight, size, and shape of particles using the sieve method [28]. [33]. They were protected from deformities during clenching using metal (1.0 mm in thickness) and rubber (1.2 mm in thickness) disks in both sides.…”

Assessment of masticatory muscle activity and occlusion time in patients with advanced tooth wear

“…[7][8][9] Numerous studies have shown an almost linear correlation between EMG potentials and the occlusal force. [10][11][12] It has also been claimed that there is a close correlation between muscle response to force and the location of a contact force in occlusion. [13][14][15][16] Although, knowledge of occlusal contacts of both dental arches in the centric occlusion is necessary for any discussion of occlusal relations for the natural dentition and restorations, there is no consensus how to measure occlusion.…”